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The introduction of pathogens into swine breeding herds can occur through a variety of contacts involving people, animals, vehicle or various supplies. Appropriate biosecurity is critical to mitigate these risks. A retrospective study was conducted to describe contacts with swine breeding sites over a one-month period and to evaluate their association with biosecurity measures and site characteristics. As part of a larger project, sites which had a recent porcine reproductive and respiratory syndrome virus introduction were selected. A questionnaire, logbooks and pig traceability system were used for collecting data relative to persons or supplies entering the breeding unit, live pig transportation, service vehicles, other animal species, neighboring pig sites and manure spreading around the site. The 84 sites investigated had a median sow inventory of 675. A median of 4 farm staff and 2 visitors entered the breeding unit at least once over the one-month period. A total of 73 sites (87%) received visitor(s), mostly from maintenance and technical services. All sites received at least 3 supply deliveries (median of 8) including semen (99% of sites), small material and/or drugs (98% of sites), bags (87% of sites), and/or equipment (61% of sites). Live pig movements were observed in all sites, with a median number of 5 truck entries on the site or exits from the site. For feed mill, rendering and propane trucks, at least one entry was noted in ≥ 61% of sites. For all service vehicle categories except feed mill and manure vacuum trucks, a single service provider was involved in each site. Dogs and cats were banned from all sites, but wild birds were observed in 8% of sites. Manure spreading within a 100 m radius of pig units was noted in 10% of the sites. With a few exceptions, biosecurity measures were not associated with the frequency of contacts. A 100-sow increase in sow inventory was associated with an increase of 0.34 in the cumulated number of staff entering the breeding unit, of 0.30 in the number of visitors and of 0.19 in the number of live pig movements. Live pig movements were also positively associated with vertically integrated farrow-to-wean (vs. independent farrow-to-wean) production and time interval of 4 weeks or more between farrowing (vs. less than 4). Considering the variety and frequency of contacts observed, biosecurity should be meticulously applied in all breeding herds to prevent endemic and exotic disease introduction., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Canine blood donors can be infected by various vector-borne or other pathogens that could be an important cause of morbidity and death in transfusion recipients., Hypothesis/objectives: To estimate and predict positivity to transmittable blood-borne pathogens in blood units collected from blood donor dogs in Canada., Animals: Six thousand one hundred and fifty blood units from 1914 active blood donors registered to the Canadian Animal Blood Bank (CABB) between March 2010 and December 2016., Methods: A registry-based retrospective study. Blood units were screened by SNAP 4Dx/4Dx Plus and PCR panel tests. Information on blood donors and test results were extracted from multiple databases and collated. Logistic regressions were used to predict blood unit positivity., Results: Of 1779 blood units, 0.56% were antibody-positive for Anaplasma phagocytophilum/platys and 0% for Ehrlichia canis/ewingii. After exclusion of antibody-positive units to Anaplasma spp., 1.1% of 6140 blood units were PCR-positive to Anaplasma phagocytophilum, Bartonella spp., Brucella canis, "Candidatus Mycoplasma haematoparvum," Mycoplasma haemocanis, or a combination of these pathogens. Babesia spp., Ehrlichia spp., and Leishmania spp. were not detected. Units from the first blood collection from a dog had higher odds of testing PCR-positive (P < .001) for at least 1 pathogen than units from subsequent collections., Conclusions and Clinical Importance: Although our study indicates a low probability of detecting blood-borne pathogen in blood units collected by this Canadian blood bank, the presence of positive units highlights the importance of the preemptive identification and screening of blood units from healthy blood donors for safe blood banking, especially in first-time donors., (© 2021 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine.)

Australia, home to the iconic dingo, is currently free from canine rabies. However northern Australia, including Indigenous communities with large free-roaming domestic dog populations, is at increased risk of rabies incursion from nearby Indonesia. We developed a novel agent-based stochastic spatial rabies spread model to evaluate the potential spread of rabies within the dingo population of the Northern Peninsula Area (NPA) region of northern Australia. The model incorporated spatio-temporal features specific to this host-environment system, including landscape heterogeneity, demographic fluctuations, dispersal movements and dingo ecological parameters-such as home range size and density-derived from NPA field studies. Rabies spread between dingo packs in nearly 60% of simulations. In such situations rabies would affect a median of 22 dingoes (approximately 14% of the population; 2.5-97.5 percentiles: 2-101 dingoes) within the study area which covered 1,131 km2, and spread 0.52 km/week for 191 days. Larger outbreaks occurred in scenarios in which an incursion was introduced during the dry season (vs. wet season), and close to communities (vs. areas with high risk of interaction between dingoes and hunting community dogs). Sensitivity analyses revealed that home range size and duration of infectious clinical period contributed most to the variance of outputs. Although conditions in the NPA would most likely not support a sustained propagation of the disease in the dingo population, due to the predicted number of infected dingoes following a rabies incursion and the proximity of Indigenous communities to dingo habitat, we conclude that the risk for human transmission could be substantial., Competing Interests: The authors have declared that no competing interests exist.

Objective: This survey aimed to understand hunting practices involving domestic dogs in remote Indigenous communities in northern Australia and, in the context of disease transmission, describe the domestic-wild dog interface and intercommunity interactions of hunting dogs during hunting activities., Methods: A cross-sectional survey of 13 hunters from communities of the Northern Peninsula Area (NPA) of Queensland gathered information on demographics of hunters and hunting dogs, hunting practices and past encounters with wild dogs during hunting trips. Social networks that described the connections of hunters between NPA communities from hunting expeditions were developed., Results: Most hunters interviewed were not aware of any diseases that could be transmitted to dogs (n = 11) or humans (n = 9) from wild animals while hunting. More than half (n = 7) of the respondents had experienced at least one wild dog encounter during hunting in the year prior to the interview. A map of the relative risk of interactions between wild and hunting dogs during hunting trips allowed the identification of high-risk areas in the NPA; these areas are characterised by dense rainforests. The social networks at the community level resulted in relatively large density measures reflecting a high level of intercommunity connectedness., Conclusions: This study contributes to our knowledge of Australian Indigenous hunting practices and supports the potential for disease transmission at the domestic-wild dog interface and intercommunity level through contacts between hunting dogs during hunting activities. Insights from this study also highlight the need for educational programs on disease management in Indigenous communities of northern Australia., (© 2019 Australian Veterinary Association.)

Jamestown Canyon and snowshoe hare viruses are two emerging human pathogens associated with cases of neuroinvasive disease in North America. This study aimed to identify environmental and individual risk factors for seropositivity to these arboviruses in humans and pet dogs from Québec, Canada, 2012-2014. In humans, areas with moderate densities of white-tailed deer (Odocoileus virginianus) were associated with higher odds of seropositivity compared with areas with low densities of white-tailed deer (OR 2.50, P = 0.009) and odds of seropositivity were higher in males than in females (OR 2.03, P = 0.016). Among humans reporting more than 10 mosquito bites weekly, the odds of being seropositive were 4.44 times higher (P = 0.004) for people living in hardwood forested areas. Exposure to areas with coniferous forests was identified as the main environmental risk factor for seroconversion in dogs (OR 2.39, P = 0.04). These findings may help target further public health research, diagnostic and surveillance efforts in Canada.

The identification of specific environments sustaining emerging arbovirus amplification and transmission to humans is a key component of public health intervention planning. This study aimed at identifying environmental factors associated with West Nile virus (WNV) infections in southern Quebec, Canada, by modelling and jointly interpreting aggregated clinical data in humans and serological data in pet dogs. Environmental risk factors were estimated in humans by negative binomial regression based on a dataset of 191 human WNV clinical cases reported in the study area between 2011 and 2014. Risk factors for infection in dogs were evaluated by logistic and negative binomial models based on a dataset including WNV serological results from 1442 dogs sampled from the same geographical area in 2013. Forested lands were identified as low-risk environments in humans. Agricultural lands represented higher risk environments for dogs. Environments identified as impacting risk in the current study were somewhat different from those identified in other studies conducted in north-eastern USA, which reported higher risk in suburban environments. In the context of the current study, combining human and animal data allowed a more comprehensive and possibly a more accurate view of environmental WNV risk factors to be obtained than by studying aggregated human data alone.